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Megasquirt 2 tacho help needed
r1_pete - 7/5/16 at 07:38 PM

Anyone know if there is a way to test the tach output on a ms2 extra?

Ive tried both the resistor and relay coil wiring and the tach will not run.

The tach is good it ran fine on the megajolt.

Any help appreciated.


big-vee-twin - 7/5/16 at 08:13 PM

This set up will work, takes signal direct from the coils. I didn't use the MS2 tacho output.


[img] tachometer diodes
tachometer diodes
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r1_pete - 7/5/16 at 09:33 PM

Cheers, yes I think I'll give that a go, the coil wires pass by the tach so can quite easily tap into them.


ashg - 8/5/16 at 01:50 PM

if the tach worked off the tach pin on the edis then it should work directly off the tach pin on the ms. did you actually build the tach circuit and check the output settings in the ms software?


r1_pete - 8/5/16 at 04:08 PM

I didn't build the MS2, its an extraefi unit, the docs say it may need a 12v supply and pull up resistor or relay coil.


40inches - 9/5/16 at 01:58 PM

I contacted SPA (I have a KitDash) and Phil at Extra EFI, regarding wiring the Tacho.
SPA said to swop the wiring over so that the tacho earth is connected to the MS2 tacho wire. Phil said it will be OK, so I have done it this way.
Should add that I haven't started the engine yet

[Edited on 9-5-16 by 40inches]